LEDs are energy-efficient and environmentally friendly, and are used in a wide range of applications. The LEDs are not only disposed in products in daily life such as general lighting, displays of computers or portable electronic devices, billboards, works of art and applications thereof, but also used in some particular semiconductor processes as the lights sources. For example, ultraviolet (UV) LEDs are used in ultraviolet exposure machine and the manufacture of UV light panels.
Generally, a LED chip is disposed on a ceramic or metal substrate, and the LED chip is packaged and encapsulated by an encapsulation material to form a package structure, so as to prevent the aging of the chip caused by the direct exposure in the air atmosphere. According to the relative location between a light emitting surface and an installation surface, which is connected to an external component, after a package structure of a LED chip is electrically connected to the external component, the LED structures can be dived into two types, one is direct lighting LED structure of which the light emitting surface and the installation surface are positioned oppositely, and the other one is edge lighting LED structure of which the light emitting surface and the installation surface are, for example, perpendicular to each other. Whatever the structure is, it is desired to develop a unit structure that exhibits a maintained or improved product yield and electrical performance, and has a good alignment precision and assembly efficiency when it is bounded with an external component. Further, it is preferred that the structure can be manufactured by a method having simple steps and being suitable for mass production.